I think "Train Wreck" love happens to those who don't go through life with their eyes and ears wide open. I spent years in the entertainment industry and there are always the talentless, lazy parasites who want to live off of you. A few years of that and you go through life with your eyes and ears wide open, you deliberately listen to the whispered conversation in the corner, you become a human lie detector and you always "trust but verify".
The reality is that people that want to use you broadcast their intentions before their activities begin. You just ignore the signs because you "love" them.
It's like the story of Doug and the married/pimped hooker. Only a fool like Doug would be so deluded as to believe that she "loved" him.
I can tell you exactly the moment that I realized that my ex-wife was no longer in love with me. She wanted a lifestyle that was "exciting" because she enjoyed "hanging" with the clients my law practice was defending. When I "betrayed" her by going to the other side, she could no longer love me.
I'm sure that it's a common refrain. One person has one set of values, the other person has a different set of values - sometimes it doesn't matter that the couple's values are different, sometimes it does matter.
Personally, I think that proving your "love" to a person by being something that you are not is always going to result in unhappiness. You can only maintain the facade, resist expressing the resentment for so long.